%%%-------------------------------------------------------------------
%%% File        : filter.erl
%%% Author      : Fyodor Ustinov <ufm@ufm.su>
%%% Description : MailEr Project
%%%               Filter service
%%%
%%% Created :  2 Sep 2009 by Fyodor Ustinov <ufm@ufm.su>
%%%-------------------------------------------------------------------
-module(filter).
-define(SERVER, filter).

-behaviour(gen_server).

%% API
-export([start_link/0]).

%% gen_server callbacks
-export([init/1, handle_call/3, handle_cast/2, handle_info/2,
	 terminate/2, code_change/3]).

-record(state, {}).
-include("mailer.hrl").

%%====================================================================
%% API
%%====================================================================
%%--------------------------------------------------------------------
%% Function: start_link() -> {ok,Pid} | ignore | {error,Error}
%% Description: Starts the server
%%--------------------------------------------------------------------
start_link() ->
    gen_server:start_link({local, ?SERVER}, ?MODULE, [], []).

%%====================================================================
%% gen_server callbacks
%%====================================================================

%%--------------------------------------------------------------------
%% Function: init(Args) -> {ok, State} |
%%                         {ok, State, Timeout} |
%%                         ignore               |
%%                         {stop, Reason}
%% Description: Initiates the server
%%--------------------------------------------------------------------
init([]) ->
    {ok, #state{}}.

%%--------------------------------------------------------------------
%% Function: %% handle_call(Request, From, State) -> {reply, Reply, State} |
%%                                      {reply, Reply, State, Timeout} |
%%                                      {noreply, State} |
%%                                      {noreply, State, Timeout} |
%%                                      {stop, Reason, Reply, State} |
%%                                      {stop, Reason, State}
%% Description: Handling call messages
%%--------------------------------------------------------------------

%%%%%%%%%%%%%%%%%%%%%%%%%%%% SMTPD Filters %%%%%%%%%%%%%%%%%%%%%%%%%%%

handle_call({smtpd, get_filter}, _From, State) ->
    F = fun(Cmd, M) ->
		gen_server:call(filter,{'SMTPD', Cmd, M})
	end,
    {reply, {ok, F}, State}
;

%%
%% -- NOOP Filter --
%%
handle_call({smtpd, noop, M}, _From, State) ->
    {ok, Sanity} = M(get_sanity,[]),
    Rc = if
	     Sanity < -10 ->
		 M(change_sanity, -1),
		 {reply, {stop, "554 Bye."}, State};

	     Sanity < -5 ->
		 M(change_sanity, -1),
		 {reply, {error, "554 STOP DO IT!"}, State};
	     true ->
		 M(change_sanity, -1),
		 {reply, ok, State}
	 end,
    Rc
;


%%% catch unknown commands
handle_call({Sys, Cmd, _M}, _From, State) ->
    io:format("Filter? ~p: '~p' '~p'~n",[Sys, Cmd, State]),
    {reply, ok, State}
;

handle_call(_Request, _From, State) ->
    Reply = ok,
    {reply, Reply, State}
.

%%--------------------------------------------------------------------
%% Function: handle_cast(Msg, State) -> {noreply, State} |
%%                                      {noreply, State, Timeout} |
%%                                      {stop, Reason, State}
%% Description: Handling cast messages
%%--------------------------------------------------------------------
handle_cast(_Msg, State) ->
    {noreply, State}.

%%--------------------------------------------------------------------
%% Function: handle_info(Info, State) -> {noreply, State} |
%%                                       {noreply, State, Timeout} |
%%                                       {stop, Reason, State}
%% Description: Handling all non call/cast messages
%%--------------------------------------------------------------------
handle_info(_Info, State) ->
    {noreply, State}.

%%--------------------------------------------------------------------
%% Function: terminate(Reason, State) -> void()
%% Description: This function is called by a gen_server when it is about to
%% terminate. It should be the opposite of Module:init/1 and do any necessary
%% cleaning up. When it returns, the gen_server terminates with Reason.
%% The return value is ignored.
%%--------------------------------------------------------------------
terminate(_Reason, _State) ->
    ok.

%%--------------------------------------------------------------------
%% Func: code_change(OldVsn, State, Extra) -> {ok, NewState}
%% Description: Convert process state when code is changed
%%--------------------------------------------------------------------
code_change(_OldVsn, State, _Extra) ->
    {ok, State}.

%%--------------------------------------------------------------------
%%% Internal functions
%%--------------------------------------------------------------------

    
